Making peroxidic compounds



Patented Nov. 3, 1942 UNITED STATES PATENT OFFICE 2,301,124 Mama rcaoxmrc COMPOUNDS Vaman R. Kokatnur, New York, and Edward S. Johmon, New Rochelle, N. Y., assignors to Autoxygen, 'Inc., New York, N. Y., .a corporation of New York No Drawing. hpplication August so, 1933, Serial No. 227,514

6 Claims. 260-406) The present invention relates to the process of producing peroxidic compounds and particularly to the production of such compounds from fatty materials which are solid and of the consistency of butter at ordinary temperatures, with melting point from 28 C. up.

peratures.

The peroxidic compounds of the buttery materials, when not associated with peroxides of acids lower than 10 carbon atoms, have many advantages over those produced in prior art from coconut oil.

They are extremely stable and approach in with our present invention are more suitable. for use in cosmetics and medicinal applications.-

The active oxygen of these compounds is many hundred times more powerful than the oxygen -'of inorganic peroxidic compounds, as well as organic peroxidic compounds which are insoluble in water, like benzoyl peroxide. From the standpoint of phenol potency based on the oxygen content in dilution, they range from several hundred to 1500 times more powerful than carbolic acid. Theypromote the-growth of enzymes, although they are deadly to pathogenic bacteria. i

It is a well known fact that mixed peroxidic compounds are generally unstable. Hydrogen peroxide when mixed with other oxidizing materials depreciates very rapidly, Permanganate of potash when brought in contact with hydrogen peroxide not only instantly decomposes hydrogen stability benzoyl-peroxide which is recognized as a standard of stability.

They are almost substantially non-oxidizing in comparison with peroxidic compounds known heretofore. In this connection it should be remembered that while inorganic peroxidic compounds act both as reducing and oxidizing agents, the organic peroxidic compounds known in prior art have been substantially oxidizing agents only. The peroxidic compounds of the buttery materials are low in oxidizing power compared with the organic peroxides known heretofore.

Not only are these compounds low in oxidizing power, but they definitely act as inhibitors ofoxidation. Thus they can be used in inhibiting rancidity, in the prevention of gum-formation in petroleum oils and of aging phenomena.

From the bacteriological standpoint they are many times more deadly than peroxi ic compounds of coconut oil and peroxidic compounds made from phthalic, malic, fumarlc, camphoric and succinic acids. Thus, peroxidic compounds made from stearic acid or from the total acids of cocoa butter or from the chaulmoogric or hydnocarpic acids, are many times more germicidal than the peroxidic compounds of the total acids of coconut oil. Benzoyl-peroxide is absolutely inert from the germicidal standpoint. For this peroxide, but-in the process destroys itself. This fact has been made use of in the analysis of hy-' drogen peroxide by permanganate of potash.

In a prior patent of Kokatnur and Stoddard, No. 1,718,609, mixed peroxidic compounds of the total fatty acids of coconut oil were first described. Known methods of producing the peroxidic compounds in general are by means of either 1) acid anhydrides, or (2) acid chlorides. Both these methods are in substance very old.

The main novelty in our present process consists in the adjustment of conditions, the order of steps and the concentration primarily of the alkali used. Prior patents of Kokatnur disclose that the mixed peroxidic compounds of the total fatty acids of coconut oil, contrary to the com-.

mon belief, are relatively stable. They also disclose that the yield of such peroxidic compounds is almost quantitative when the alkali concentration is adjusted to a given degree.

We have now found that coconut oil peroxides, although relatively stable, are not stable enough from a commercial standpoint and this may be one reason why they have not found practical use. Further, contrary to the disclosure in these prior patents, the yield of peroxidic compounds 'of buttery materials is very small, if the method of these patents is followed. Experimental work has indicated that low yields of peroxidic compounds of buttery materials are due to the inclusion of the acid chloride by a crust of the newly formed solid peroxidic compound. It would be somewhat like the deposit on' a surface by a solid substancedissolved in a volatile solvent, during evaporation of the solvent. To under stand the difficulty one may visualize a globule reason peroxidic compounds made in accordance f n acid chloride liquid at ordinary t p tures) in reaction at the suriacewith an inor= garlic peroxide. The newly formed peroxidic material becomes a solid.shel1 with a liquid core of acid chloride} There is lack oi minute sub-division at contact.

Whether this theory is true or not, the fact remains that the yields of peroxldic compounds from buttery materials are very low, that is, of the order of 25% to 40%. I that prior methods of producing these compounds And we have found have to be radically modified it better yields are to be obtained. For this purpose we have found it extremely advantageous either to use a solvent i'or acid chloride and hydrogen peroxide, or to decrease the particle size of the slobule or the acid chloride by dissolving in an inert solvent,

- so that a homogeneous precipitate, not encrusted globules, is produced. i

We have found that water-soluble alcohols, iratones and ethers are satisfactory as neutral medie. As neutral media for reducing the size of the acid chloride globule, we have found low boiling hydrocarbons both of the aliphatic and the accrues after as cocoa butter chloride) with an average molecular weight of around 300, and 110 to 115 parts by volume of a 10% solution of caustic soda are added simultaneously in substantially equal. amounts gradually and piece-meal. During this addition the agitation is continued vigorously, taking care that the temperature does not er;= ceed 35 C. to 40 C. The addition of the cocoa butter chloride and the caustic soda solutions is so adjusted as to occupy about one hour. By this addition afcritical alkalinity is maintained in the solution throughout the experiment. After about one-half hour the agitation may be dis- "continued ii round desirable. The end of the reaction is determined by the color and the state of the subdivision of the reaction mass. The color is generally slightly brownish white and the original liquid thickens uniformly without any lumps. At the end of the reaction the reaction iats with butter-like consistency. These fatty acids are often available on the market and are generally prepared by the ordinary saponiflca.-, tion process or by the Twitchell process. We, however, prefer to use fatty acids prepared from non-aqueous saponification or splitting as disclosed in U. S. P. 1,913,454 of July 7, 1931. We have found that the fatty acids produced by this method yield more stable and purer peroxidic compounds than those prepared from ordinary iatty acids available on the market or from those prepared by the ordinary saponification or Twitchell splitting method.

In trying to account for this strange difl'erence, we have come to the conclusion that in the ordinary method of saponification or splitting by watery solutions, certain changes in fatty acids occur. What the nature of such changes is, we have so far not been able to determine. We are inclined to believe that during the long boiling operation in the presence of water possibly certain hydroxylation reactions take place. Whether this is so or not, the fact remains that the peroxidlc compounds produced from acids which in turn are produced by non-aqueous saponifica- I Example I In a suitable vessel fitted with agitator, -35

mass or mother liquor is i'lltered and washed with cold water, temperature between 10 and it C. containing 1 to 2% of acetone. The washinu is continued until the wash liquor shows no trace of acid chloride or of free hydrogen peroxide; The wet pulverulent and white crystalline material is dried at a temperature not to exceed 37 until it is free from water or acetone. The puri= ty of the material is about 75% and the yield is about 80% of the theoretical. This material may be recrystallized from solvents like petroleum ether, benzene or acetone, etc. to produce a material of 09% purity. If the solution during recrystallization is found to be acidic it should be neutralized and the solvent separated and dried before recrystallizating the peroxide product. To avoid losses of acetone 9. closed vessel with a distilling as well as a reflux attachment should be used. I

ample l, 30 to 40' parts by volume of hydrogen peroxide, strength 28% to 30% by weight, and 200 parts by volume of commercial benzene are added. It should be noted that the hydrogen parts by volume of 28 to 30% hydrogen peroxide,

' and parts by volume of acetone are added.

To this mixture of hydrogen'peroxide and acetone 100 parts by volume of the acid chloride of the total acids of cocoa butter (designated hereperoxide is not soluble in benzene and being heavier stays at the bottom. To this, after the agitation is started, 126 parts of 10% sodium hydroxide solution and 100 parts by volume oi cocoa butter chloride areadded slowly and simultaneously, keeping the alkali solution, however,

in slight excess throughout the addition period.

During the addition the temperature should not be allowed to go substantially above 10 6. and the time of addition and operation should be approximately an hour. During the operation the benzene dissolves the cocoa butter chloride instantly and this solution comes in contact with the dispersing hydrogen peroxide and the added caustic soda solution. The reaction seems to be instantaneous and the peroxide separates in a crystalline mass forming with benzene what appears to be a combination as benzene oi crystallization and appearing as a homogenous viscous crystalline slurry.

During the operation the alkali should be added uniformly in excess. The agitation may be stopped after about one-half hour. At the end of the reaction the excess of alkali is neutralized by dilute hydrochloric acid and the excess of benzene distilled under vacuum at a temperature When most of the benzene is not to exceed 40". substantially removed, the reaction slurry is filtered and washed with water containing about hydrogen peroxide. Without this small amount of hydrogen peroxide in the water, the

washing and filtration becomes well nigh impossible. After the washing is completed the filter cake is dried as mentioned in Example I. The purity of this material is between 85% and 90%. The yield is between 85% and 88% of the theoretical.

The term, inert diluent, as used herein, is intended to include solvents which are not acted The expressions, integral mixing or fine division or dispersion as used herein are meant to signify mixing of two immiscible materials in a very thorough intimate manner either by the use of a solvent, a diluent, or by merely a mechanical action.

We claim:

l. The process of producing peroxidic coinpounds of fatty acids from natural fats of butterlike consistency containing acids of more than carbon atoms only, comprising reacting the acid chlorides of the said fatty acids with hydrogen peroxide of about 30% strength, the reacting materials being in a finely divided condition, and neutralizing the chlorine acids as fast as they are produced during the reaction and at a temperature below about 50 C. while maintaining a predetermined slight alkalinity.

2. The process of producing peroxidic com- .pounds of fatty acids from natural fats of butteras they are produced during the reaction by the progressive addition of alkaline solution whose concentration slightly exceeds that necessary to completely neutralize the chlorine of the acid chloride during the reaction and at a temperature below'about 50 C,

3. The process of producing peroxidic com- I pounds of fatty acids from natural fats of butterlike consistency containing acids of more than 10 carbon atoms only, which comprises adding progressively and simultaneously the acid chlorides of the said fatty acids and an alkaline peroxide solution in an inert solvent of said acid chlorides with agitation, the said chlorides and. alkaline solution being added. in proportions so as to keep the reaction mass slightly alkaline throughout the process and at a temperature not to exceed about 50 C.

4. The process of producing peroxidic compounds of mixed fatty acids derived from cocoa butter which comprises reacting the acid chlorides of the said fatty acids with hydrogen peroxide of about 30% strength, the reacting materials being in a finely divided condition, and neutralizing the chlorine acids as fast as they are produced during the reaction and at a temperature below about 50 C. while maintaining a predetermined slight alkalinity.

5. The process of producing peroxidic compounds of mixed fatty acids derived from cocoa butter which comprises reacting the acid chlorides of the said fatty acids with hydrogen peroxide of about 30% strength in the presence of an inert solvent which has a solvent action on at least said acid chlorides, and neutralizing the chlorine acids as fast as they are produced during the reaction and at a temperature below about 0., while maintaining a predetermined slight alkalinity.

6. The process of producing peroxidie compounds of mixed fatty acids derived from cocoa butter which comprises reacting the acid chlorides of the said fattyacids with hydrogen peroxide of about 30% strength in the presence of an inert solvent of said acid chlorides, and new tralizing the chlorine acids as fast as they are produced during the reaction by the progressive addition. of alkaline solution whose concentration exceeds that necessary to completely neutralize the chlorine of the acid chloride during the reaction and at a temperature below about 50 C.

VAMAN R. KOKATNUR. EDWARD s. JOHNSON. 

